Method of using a catheter tunneler adapter

ABSTRACT

An adapter assembly ( 120 ) for connecting a catheter assembly ( 50,52 ) to a tunneler ( 110 ) having a generally tubular body ( 122 ) having a first end ( 124 ), a second end ( 126 ) and a longitudinal axis ( 128 ) extending therethrough between the first end and the second end. The first end ( 124 ) of the adapter is constructed to engage the proximal end ( 114 ) of a trocar ( 110 ). The second end ( 126 ) of the adapter is constructed to releasably engage at least one catheter lumen ( 50,52 ). A slider ( 140 ) is disposed about the adapter ( 120 ) and is longitudinally slidable along the adapter. When the slider ( 140 ) is slid towards the second end ( 126 ) of the adapter, the slider engages a plurality of legs ( 134   a - 134   d ) on the adapter and biases the plurality of legs toward each other and the longitudinal axis of the adapter. A method of subcutaneously tunneling a catheter using the adapter assembly is also described that comprises inserting a catheter into a patient, connecting the proximal end of a trocar to the adapter assembly, releasably restraining at least one lumen of the catheter in the adapter, and tunneling the assembly.

CROSS REFERENCE TO RELATED APPLICATION

This application is a Divisional application of U.S. Ser. No. 10/889,816filed Jul. 13, 2004 which claims the benefit of U.S. ProvisionalApplication No. 60/487,926, filed Jul. 17, 2003 and U.S. ProvisionalApplication No. 60/495,077, filed Aug. 14, 2003.

FIELD OF THE INVENTION

The present invention relates to a tunneler device for subcutaneouslytunneling at least one catheter lumen under a patient's skin.

BACKGROUND OF THE INVENTION

Catheters for the introduction or removal of fluids may be located invarious venous locations and cavities throughout the body of a patientfor introduction of fluids to the body or removal of fluids from thebody. Such catheterization may be performed by using a single catheterhaving multiple lumens. A typical example of a multiple lumen catheteris a dual lumen catheter in which one lumen introduces fluid and theother lumen removes fluid. An example of such a multiple lumen catheteris the SPLIT STREAM® catheter, sold by Medical Components, Inc. ofHarleysville, Pa.

Generally, to insert any catheter into a blood vessel, the vessel isidentified by aspiration with a long hollow needle in accordance withthe well-known Seldinger technique. When blood enters a syringe attachedto the needle, indicating that the vessel has been found, a thin guidewire is then introduced, typically through a syringe needle or otherintroducer device into the interior of the vessel. The introducer deviceis then removed, leaving the end portion of the guide wire that has beeninserted into the vessel within the vessel and the opposing end of theguide wire projecting beyond the surface of the skin of the patient. Atthis point, several options are available to a physician for catheterplacement. The simplest is to pass a catheter into the vessel directlyover the guide wire. The guide wire is then removed, leaving thecatheter in position within the vessel. However, this technique is onlypossible in cases where the catheter is of a relatively small diameter,made of a stiff material, and not significantly larger than the guidewire. For example, this technique may be used to insert small diameterdual lumen catheters into a patient. If the catheter to be inserted issignificantly larger than the guide wire, a dilator and sheath assemblyis passed over the guide wire to enlarge the hole. The guide wire anddilator are then removed, and the catheter is then inserted through thesheath and into the vessel. The sheath is then removed by peeling thesheath from around the catheter while pulling the sheath from thevessel.

For chronic catheterization, in which the catheter is intended to remaininside the patient for an extended period of time, such as for weeks oreven months, it is typically desired to subcutaneously tunnel thecatheter using various tunneling techniques. The catheter is typicallytunneled into the patient prior to inserting the catheter into thepatient's vein.

However, depending on the patient or the implanting surgeon's skill,there may be times when it is more advantageous to perform the tunnelingafter the catheter is implanted in the patient. For some catheters,though, such as multiple lumen catheters with a hub and catheters withbonded luers on the proximal ends of the catheters, it is impractical toperform the tunneling after the catheter is installed in the patient. Itwould be beneficial to provide a tunneling tool that provides a surgeonwith alternative installation procedures for subcutaneously tunnelingthe catheter, either before or after the distal portion of the catheteris placed in the patient's blood vessel, that better suit either thepatient's needs or the surgeon's skills.

In order to be able to perform the tunneling after the distal end of thecatheter assembly is inserted into the patient, the proximal ends ofeach catheter must be attached to a tunneler device adapted to pull theproximal end of each catheter through the tunnel. After tunneling, theproximal ends of the catheters must be disconnected from the tunnelerdevice connected to a catheter hub. It would be beneficial to provide atunneler device that allows for the simultaneous tunneling of theproximal ends of each catheter in a multi-lumen catheter assembly.Likewise, it would be beneficial to provide a tunneler device that wouldallow for the simultaneous tunneling of the distal ends of each catheterin a multi-lumen catheter assembly.

SUMMARY OF THE INVENTION

The present invention provides a catheter tunneler adapter assembly. Theassembly comprises an adapter that is adapted to be connected to atrocar and releasably connected to a catheter. The assembly is used forsubcutaneously tunneling a catheter through a patient's flesh during theinsertion of a long term hemodialysis catheter. The adapter has a distalend, a proximal end and a tubular body extending therethrough betweenthe distal and proximal ends. The tubular body defines a longitudinalpassageway along the longitudinal axis of the adapter. The distal end ofthe adapter is adapted to connect to the trocar. The connection of theadapter to the trocar can be either releasable or fixed. The proximalend of the adapter is adapted to releasably connect to a catheter.Generally the proximal end of the adapter has a plurality of taperedlegs extending proximally from tubular body of the adapter. The legspreferably have stops located at the most proximal end of the adapterand there are preferably a plurality of ribs extending from the legsinward towards the longitudinal axis of the adapter. There is, disposedaround the adapter, a slider that is sized to frictionally fit aroundthe adapter and slide back and forth longitudinally along the adapter;the slider ensheathes the adapter and is free of radially outwardprojections, thereby presenting a minimal transverse dimension andgenerally smooth continuous outer surface that facilitates its beingpulled through the subcutaneous tunnel with the catheter and adapter.The range of motion of the slider is limited by the stops at theproximal end and at least one bump located on the outside of theadapter's tubular body. Preferably, at least one of the plurality oflegs is tapered in such a way that the legs are thicker at the proximalend of the adapter. The adapter is operated by inserting at least onecatheter lumen into the proximal end of the adapter and sliding theslider proximally so that the slider compresses the tapered legs towardsthe longitudinal axis and each other, thereby restraining the catheterwithin the longitudinal passageway. Either the proximal end or thedistal end of the catheter may be inserted into the adapter. Once thecatheter is restrained within the adapter, the assembly is tunneled,trocar first, according to techniques well known to those skilled in theart.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated herein and constitutepart of this specification, illustrate the presently preferredembodiments of the invention, and, together with the general descriptiongiven above and the detailed description given below, serve to explainthe features of the invention. In the drawings:

FIG. 1 is a perspective view of a catheter tunneler adapter, accordingto an embodiment of the present invention.

FIG. 2 is an exploded side view, partially in section, of the cathetertunneler adapter in FIG. 1 and showing a catheter end to be insertedinto the adapter.

FIG. 2 a is an enlarged side view, partially in section, of the cathetertunneler adapter in FIG. 2.

FIG. 3 is an end view of the adapter only of the catheter tunneleradapter in FIG. 1.

FIG. 4 is a side view, in section, of the adapter and slider of thecatheter tunneler adapter in FIG. 1, with a multi-lumen catheterinserted therein.

FIG. 5 is a perspective view of an alternate embodiment of a cathetertunneler adapter, according to the present invention.

FIG. 6 is an end view of the adapter only of the catheter tunneleradapter in FIG. 5.

FIG. 7 is a perspective view of an alternate embodiment of an adapteronly of a catheter tunneler adapter, according to the present invention.

FIG. 8 is a side view, in section of an alternate embodiment of acatheter tunneler adapter, according to the present invention, with atrocar being inserted therein.

FIG. 9 is a side view, in section of an alternate embodiment of acatheter tunneler adapter, according to the present invention, with aslider being slid thereupon.

FIG. 9 a is a cross-sectional view of the catheter tunneler adapter ofFIG. 9.

DETAILED DESCRIPTION OF THE INVENTION

In the drawings, like numerals indicate like elements throughout.Certain terminology is used herein for convenience only and is not to betaken as a limitation on the present invention. When describing orreferring to the catheter tunneler adapter, the words “proximal” and“distal” refer to directions away from and closer to, respectively, thepointed tip of the trocar that makes up a portion of the cathetertunneling assembly according to the present invention. When describingor referring to a catheter, the words “proximal” and “distal” refer todirections away from and closer to, respectively, the tip of thecatheter that is inserted in the blood vessel closest to the patient'sheart. The terminology includes the words above specifically mentioned,derivatives thereof, and words of similar import. The followingdescribes preferred embodiments of the invention. However, it should beunderstood based on this disclosure, that the invention is not limitedby the preferred embodiments described herein.

Referring to FIG. 1, a perspective view of a catheter tunneling assembly100 according to a preferred embodiment of the present invention isshown. Preferably, the catheter tunneling assembly 100 is used to tunnela distal end of a catheter assembly through a subcutaneous tunnel priorto inserting the catheter into the patient. Alternatively, the cathetertunneling assembly 100 may be used to tunnel a proximal end of thecatheter assembly through the subcutaneous tunnel either prior to orafter inserting the catheter into the patient.

Referring to FIG. 2, the tunneling assembly 100 includes a distalportion, or tunneler, such as a trocar 110, which is comprised of adistal tip 112 and a proximal end 114. Preferably, the proximal end 114includes a threaded male connection 116. Alternatively, the proximal end114 of the trocar 110 may include a female threaded connection (notshown), bulbous or barbed projections (not shown) or a notch (notshown), a ridge (not shown), or any other type of suitable connectiondevice in place of the threaded male connection 116.

The trocar 110 has an elongated body 118 that extends between the distaltip 112 and the proximal end 114. The body 118 preferably bends at apredetermined location along the length of the body 118. As shown inFIG. 2, the body 118 is bent at an angle 131 of approximately 12degrees, although those skilled in the art will recognize that the body118 may be bent more or less than 12 degrees or have no bend at all.

Referring generally to FIGS. 1-4, the tunneling assembly 100 furtherincludes a proximal portion, or adapter 120. The adapter 120 iscomprised of a generally elongated tubular body 122 having a generallycircular distal end 124, which tapers to a generally oblong proximal end126. A longitudinal axis 128 extends between the distal end 124 and theproximal end 126.

Referring to FIG. 2, the distal end 124 of the adapter 120 includes aconnection means or section for connecting the proximal end 114 of thetrocar 110 thereto. The connection means comprises a generally tubulardistal passageway 130 extending generally longitudinally through thetubular body 122 from the distal end 124 toward the proximal end 126 ofthe adapter 120. The distal passageway 130 preferably includes athreaded female connection 132 to threadingly engage the threaded maleconnection 116 on the trocar 110. Alternatively, the distal end of theadapter 120 may have a recess (not shown) to accept a notch located onthe proximal end 114 of the trocar 110, a male threaded connection to bemated to a female threaded connection on the proximal end 114 of thetrocar 110 or any other suitable connection device adapted to connectthe adapter to the trocar 110.

Referring to FIGS. 1-3, the proximal end 126 of the adapter 120 includesa connection means for connecting a plurality of catheter lumens 50, 52thereto. The connection means comprises a plurality of legs 134 a, 134b, 134 c, 134 d, which extend distally from the distal portion 124. Aproximal portion of each leg 134 a, 134 b, 134 c, 134 d includes a stopportion 135 a, 135 b, 135 c, 135 d, respectively, that extends away fromthe longitudinal axis 128. A longitudinal slot 136 a, 136 b, 136 c, 136d extends between each of adjacent legs 134 d, 134 a, 134 b, 134 c, 134d, respectively. While four legs 134 a, 134 b, 134 c, 134 d and fourslots 136 a, 136 b, 136 c, 136 d are shown, those skilled in the artwill recognize that more or less than four legs 134 a, 134 b, 134 c, 134d and four slots 136 a, 136 b, 136 c, 136 d may be used.

As seen in FIG. 3, each leg 134 a, 134 b, 134 c, 134 d has a generallyarcuate cross-section. A generally oval-shaped proximal passageway 138is formed within a space defined by the legs 134 a, 134 b, 134 c, 134 dand the slots 136 a, 136 b, 136 c, 136 d. The proximal passageway 138extends distally of the legs 134 a, 134 b, 134 c, 134 d toward thedistal passageway 130.

Referring generally to FIGS. 2-4, optionally each leg 134 a, 134 b, 134c, 134 d may include at least one, and preferably a plurality oftransverse ribs 137 that extend towards the longitudinal axis 128 intothe proximal passageway 138. The transverse ribs 137 provide additionalsurface area to frictionally engage the lumens 50, 52 when the lumens50, 52 are inserted into the distal end 126 of the adapter 120. Thetransverse ribs 137 may have a generally semi-circular cross-section, orthe transverse ribs 137 may be barbed, to facilitate insertion of thelumens 50, 52 into the proximal passageway 138, but to retard removal ofthe lumens 50, 52 from the proximal passageway 138. Those skilled in theart will recognize that the ribs 137 may be of any shape that willfacilitate the retention of the lumens 50, 52 within the proximalpassageway 128.

As shown specifically in FIG. 2 a, each leg 134 c, 134 d is taperedalong an outer surface of each leg 134 a, 134 b, distal from thelongitudinal axis 128. Although not shown, legs 134 a, 134 b preferablyhave the same taper. Each taper has a thickness “t” proximate to thedistal end 124 of the adapter 120. Each taper also has a thickness “T”,thicker than the thickness “t”, proximate to the proximal end 126 of theadapter 120. Preferably, the taper is at an angle 132, approximately 8degrees, although those skilled in the art will recognize that the angle132 may be more or less than 8 degrees. As also seen in FIG. 2, theproximal passageway 138 is in fluid communication with the distalpassageway 130, although those skilled in the art will recognize thatthe proximal passageway 138 need not necessarily be in fluidcommunication with the distal passageway 130.

Referring to FIGS. 1, 2, 2 a and 4, a surrounding component is to beplaced around and into pressing engagement with outer surfaces of theadapter proximal end when the catheter lumen is inserted thereinto, toassure that the adapter proximal end is in gripping engagement withouter surface portions of the catheter lumen. The surrounding componentmay be a locking member or slider 140 disposed on the adapter 120distally from the legs 134 a, 134 b, 134 c, 134 d and slidable between adistal position proximate to the distal end 124 of the adapter 120 and aproximal position proximate to the stops 135 a, 135 b, 135 c, 135 d.Preferably, the slider 140 is sized to frictionally engage and, due tothe taper of the legs 134 a, 134 b, 134 c, 134 d compress the legs 134a, 134 b, 134 c, 134 d towards the longitudinal axis 128 and each otheras the slider 140 is slid proximally about the adapter 120. Thoseskilled in the art will recognize that the slider 120 may have anelongated proximal portion designed to shield the distal end of thecatheter lumens 50, 52 from obstructions during insertion. An example ofsuch an elongated slider is shown in FIG. 9. Preferably, where a sliderhas an elongated proximal end, the slider covers any apertures that aredisposed about the catheter lumens 50, 52.

As shown in FIGS. 1 and 2, the slider 140 has a distal end 142, aproximal end 144 and an elongated body 146 disposed between the distalend 142 and the proximal end 144. The slider 140 is sized tofrictionally fit about the outside surface of the elongated tubular body122 of the adapter 120. The slider also can be seen to be free ofradially outward projections thereby having a minimal transversedimension, and have a generally smooth, continuous outer surface thusbeing shaped and dimensioned to be suitable for facilitating its beingpulled through the subcutaneous tunnel created by the trocar. The slider140 is retained about the adapter 120 by at least one, and preferablytwo, raised tabs 150 located on opposing sides of the body 122 of theadapter 120. The raised tabs 150 are shaped and sized to allow theslider 140 to be slid over the raised tabs 150 in a proximal directionfrom the distal end 124 to the proximal end 126 to assemble the adapter120, but restrict the movement of the slider 140 over the raised tabs150 in the distal direction once the slider 140 is slid proximally pastthe raised tabs 150. As shown in FIG. 4, the raised tabs 150 preferablyhave a gradually sloped distal surface 152 and a vertical or steeplysloped proximal surface 154. Alternatively, the raised tabs 150 may berounded or have any type of a profile that would facilitate sliding theslider 140 over the raised tabs 150 in the proximal direction andrestrict the slider 140 from sliding over the raised tabs 150 in thedistal direction. Preferably, the slider 140 and the adapter 120 areeach of unitary construction and are constructed of a material that issufficiently flexible as to allow the slider 140 to deflect enough tofit over the raised tabs 150 when a force is applied to the slider 140in the proximal direction during assembly. Preferably, in applicationswhere the adapter 120 has an oval cross-section, the slider 140 has agenerally oval cross-sectional shape to match the generally ovalcross-sectional shape of the proximal passageway 138. However, thoseskilled in the art will recognize that the adapter 120 may have across-section that is circular or some other shape and that it ispreferred that the slider 140 has a shape that corresponds to thecross-sectional shape of the adapter 120.

Referring generally now to FIGS. 1-4, during assembly of the adapterassembly 100, the slider 140 is positioned at the distal end 124 of theadapter 120. The slider 140 is then slid in a proximal direction aroundthe adapter 120 until the entire slider 140 is proximal of the at leastone raised tab 150, on the adapter 120.

Preferably, the adapter 120 and the slider 140 are constructed from apolymer, such as polypropylene or polyurethane, although those skilledin the art will recognize that the adapter 120 and the slider 140 may beof composite construction or may be constructed from other suitablematerials as well. Examples of some other preferable materials would beTEFLON polytetrafluoroethylene for the slider 140 and high densitypolypropylene for the adapter 120. Preferably, at least one of theslider 140 and adapter 120 are preferably constructed from a materialthat is rigid enough to minimize deflection and thereby restrain theslider 140 from inadvertently being slid over the raised tabs 150 in thedistal direction. The trocar 110 is preferably of unitary constructionand constructed from stainless steel. Those skilled in the art willrecognize that the trocar 110 may be constructed from any material thatis rigid enough to resist deflection during tunneling.

As seen in FIG. 2, a distal, or if preferred by the inserting physiciana proximal, end of at least one, and preferably at least two, catheterlumens 50, 52 may be disposed into the proximal passageway 138. Anexample of such catheter lumens are the lumens used on the SPLIT STREAM®catheter, sold by Medical Components, Inc. of Harleysville, Pa. Thelumens 50, 52 are insertable into the proximal passageway 138 at theproximal end 126 of the body 122. The lumens 50, 52 each have agenerally circularly shaped cross-section, necessitating the need forthe proximal passageway 138 in the adapter 120 to be generally ovalshaped in cross-section. However, it will be known to those skilled inthe art that in an application where the catheter to be tunneled has agenerally circular cross-section, an adapter with a generally circularcross-section, such as the adapter 220 shown in FIGS. 5 and 6, ispreferred. Referring back to FIG. 2, preferably, in a case where theinserting physician chooses to subcutaneously tunnel the catheter priorto insertion in the patient's vessel, if the lumen 50 is longer than thelumen 52, the distal passageway 138 is sufficiently long for both lumens50, 52 to be at least partially inserted and retained therein.

Preferably, the slider 140 is disposed in the distal position prior tothe lumens 50, 52 being inserted into the proximal passageway 138. Theslider 140 may be disposed about the adapter 120 during manufacture, orthe assembly 100 may be sold in pieces and the slider 140 may bedisposed about the adapter 120 during post-sale assembly, prior to use.Preferably, the lumens 50, 52 are inserted into the proximal passageway138 at least beyond the legs 134 a, 134 b, 134 c, 134 d, as shown inFIG. 4. The slider 140 is then slid proximally, toward the stops 135 a,135 b, 135 c, 135 d. As the slider 140 is being slid along the length ofthe legs 134 a, 134 b, 134 c, 134 d, the taper in the legs 134 a, 134 b,134 c, 134 d forces the legs 134 a, 134 b, 134 c, 134 d toward thelongitudinal axis 128 and each other, thereby decreasing the size of theproximal passageway 138 proximate to the legs 134 a, 134 b, 134 c, 134d, causing at least one of the legs 134 a, 134 b, 134 c, 134 d tofrictionally engage at least one of the lumens 50, 52 and to force thelumens 50, 52 against each other, also in frictional engagement. Thefrictional engagement between the legs 134 a, 134 b, 134 c, 134 d andthe catheter lumens 50, 52 is aided by the at least one transverse rib137. The frictional engagement of the legs 134 a, 134 b, 134 c, 134 dwith the lumens 50, 52 and of the lumens 50, 52 with each otherrestricts the lumens 50, 52 from being pulled out of the proximalpassageway 138 during tunneling. The stops 135 a, 135 b, 135 c, 135 dprevent the slider 140 from being slid off the legs 134 a, 134 b, 134 c,134 d. FIG. 4 shows the lumens 50, 52 after having been inserted intothe proximal passageway 138 as described above. While FIG. 4 shows thecatheter tunneler adapter assembly 100 that is not connected to thetunneler 110, it is preferable that the tunneler 110 is connected to theadapter 120 prior to insertion of the lumens 50, 52.

The trocar 110 is connected to the adapter 120 by inserting the proximalend 114 of the trocar 110 into the distal end 124 of the adapter 120.Those skilled in the art will recognize that the trocar 110 may beconnected to the adapter 120 before or after releasably restraining thelumens 50, 52 in the adapter 120.

To tunnel the distal end of the catheter prior to insertion of thecatheter into the patient, an incision is made in the patient's skin atthe beginning of the tunnel. The distal tip 112 of the trocar 110 isinserted into the incision and the trocar 110 is advanced subcutaneouslythrough fatty skin tissue to an exit point, such as at or near theincision site for the catheter to be inserted into the blood vesselbeing catheterized, thus defining a subcutaneous tunnel for anchoringthe catheter assembly's proximal end, the tunnel being sized to be justlarge enough for the catheter. The trocar 110 is advanced through thetissue from the incision to the exit site, pulling the adapter 120 andthe catheter lumens 50, 52 through the tunnel. As the trocar 110 exitsthe exit site, the trocar 110 may be gripped with a tool, such asforceps, and pulled from the exit site, until the entire tunnelingassembly 100 is pulled from the exit site.

At this point, the slider 140 may be slid distally toward the distal end124 of the adapter 120. Sliding the slider 140 distally allows the legs134 a, 134 b, 134 c, 134 d to separate from each other as well as moveaway from the longitudinal axis 128, and into an unbiased position,thereby allowing the lumens 50,52 to be removed from the passageway 138.The lumens 50, 52 may then be removed from the adapter 120 and insertedinto the incision site for insertion of the catheter into the vesselbeing catheterized.

Alternatively, the catheter may be retro-tunneled through a subcutaneoustunnel after the distal ends of the catheter lumens 50, 52 have beeninserted into a patient's vessel. Preferably, the catheter has adetachable hub, such as the “SPLIT STREAM” catheter disclosed in U.S.Patent Publication No. US 2004/0092863, which is owned by the assigneeof the present invention and is incorporated herein by reference in itsentirety.

As described above, when retro-tunneling the catheter, the trocar 110may be connected to the adapter 120 either before or after connectingthe catheter lumens 50, 52 to the adapter 120. Also, the slider 140 ispreferably disposed toward the distal end 124 of the adapter 120.However, those skilled in the art will recognize that the slider 140 maybe initially disposed in the center of the adapter 120 or closer to theproximal end 126 of the adapter 120, where the slider 140 would have asmaller range of travel than that of a slider 140 disposed toward thedistal end 124 of the adapter 120. With any type of fittings orextensions removed, proximal ends of the catheter lumens 50, 52 areinserted into the proximal passageway 138 in the adapter 120. The slider140 is slid distally against the stops 135 a, 135 b, 135 c, 135 d toreleasably retain the catheter lumens 50, 52 as described above and toensheathe the adapter. The distal tip 112 of the trocar 110 is theninserted into the incision site where the catheter is inserted into thevessel being catheterized, and advanced through subcutaneous fattytissue, either to a separate cut incision site, or by advancing thetrocar 110 through the skin. Preferably, a trocar 110 that is used topierce the skin of a patient will have a pointed tip 112 and a trocar110 that is tunneled to a separate incision site would have a blunt tip.As the trocar 110 exits the exit site, the trocar 110 may be grippedwith a tool, such as forceps, and pulled from the exit site, until theentire tunneling assembly 100 is pulled from the exit site.

At this point, the slider 140 may be slid distally toward the distal end124 of the adapter 120, and the proximal ends of the catheter lumens 50,52 may be removed from the adapter 120 and connected to a hub orextensions as necessary. Those skilled in the art will recognize thatthe distal end of the catheter, with lumens 50, 52, may be inserted intothe vessel being catheterized at a time either prior to or subsequent tothe above-described tunneling procedure.

While the tunneling assembly 100 is described herein as two separateparts, namely a trocar 110 and an adapter 120, those skilled in the artwill recognize that the tunneling assembly 100 may be a single part,still with a slidable slider 140.

An alternate embodiment of an adapter 220 is shown in FIGS. 5 and 6.Instead of the generally oval shaped proximal passageway 138 shown inFIG. 3, the adapter 220 of FIGS. 5 and 6 includes a longitudinal axis228 and a proximal passageway 238 having a generally circularly shapedcross-section, when a cross-sectional view is taken in a plane that isperpendicular to the longitudinal axis 228. Preferably, the slider 240that accompanies the adapter 220, also has a generally circularcross-section. The generally circularly shaped cross-section of theproximal passageway 238 is shaped to accept and releasably retain twosemi-circularly shaped lumens such as those on the SPLIT-CATH® cathetersold by Medical Components, Inc. Alternatively, the adapter 220 may beused to releasably retain a single circularly shaped lumen, such as thelumen used on the TESIO® catheter, also sold by Medical Components, Inc.The adapter 220 preferably connects to the trocar 110 in the mannerdescribed above with respect to the adapter 120, and a catheter may besubcutaneously tunneled in any of the manners described above withrespect to the adapter 120.

A third embodiment of an adapter 330 is shown in FIG. 7. The adapter 330has a distal end 332, a proximal end 334 and a longitudinal axis 342extending therethrough between the distal end 332 and the proximal end334. There is a longitudinal passageway 338 extending along thelongitudinal axis 342 between the distal end 332 and the proximal end334. The body of the adapter 330 comprises a plurality of legs 344 a,344 b, 344 c and 344 d extending longitudinally, parallel to thelongitudinal axis 342, along the adapter. Preferably, the adapter 330 isof unitary construction and has a plurality of flexible grooves 340 a,340 b, 340 c, 340 d extending longitudinally from the distal end 332 tothe proximal end 334 and located between the plurality of legs 344 d,344 a, 344 b, 344 c and 344 d. While the grooves 340 a, 340 b, 340 c,340 d are shown in FIG. 7 to be V-shaped, those skilled in the art willrecognize that grooves having a shape other than a V-shape, such as aU-shape, may also be used. Preferably, the adapter 330 has a generallyround cross-section, although those skilled in the art will recognizethat alternative embodiments may have cross-sections that are not round,such as an oval cross-section. The outside diameter of the distal end332 is smaller than the outside diameter of the proximal end 334. Thereis, located between the distal end 332 and the proximal end 334, atapered section 336, where the outside diameter of the adapter 330increases from the distal end 332 towards the proximal end 334.

During use, a slider (not shown) may be slid proximally from the distalend 332 towards the proximal end 334. As the slider is slid proximallytowards the distal end 332, the slider frictionally engages the exteriorsurface of the adapter 330, thereby compressing the proximal end 338 ofadapter 330 towards the longitudinal axis 328 and decreasing thediameter of the longitudinal passageway 338. Preferably, the innerdiameter of the slider is sized to compress the adapter 330 byfrictionally engaging the tapered portion 336 of the adapter 330 as theslider is slid proximally along the longitudinal axis 342. Preferably,the longitudinal passageway 338 has a cross-sectional area sized so thata part of a catheter may be inserted into the proximal end 334 of theadapter 330 when the slider is in the distal position and, when theslider is slid proximally to the proximal position, the cross-sectionalarea of the longitudinal passageway 338 decreases so that the part ofthe catheter inserted into the longitudinal passageway 338 isfrictionally restrained in the longitudinal passageway 338.

A fourth embodiment of the present invention is shown in FIG. 8. In thisembodiment, there is a catheter tunneler adapter assembly 400 having atrocar 410, an adapter 420 and a slider 440 slidably disposed about theadapter 420. The trocar 410 has a distal tip 412 a proximal end 414 anda longitudinal shaft 418 disposed between the distal tip 412 and theproximal end 414. Although the distal tip 412 is shown to be pointed,those skilled in the art will recognize that the distal tip 412 may beblunt. The proximal end 414 of the trocar 410 is thicker than thelongitudinal shaft 418. The thickness of the trocar 110 increases at thebeveled portion 416, located between the proximal end 414 and thelongitudinal shaft 418.

The adapter 420 is comprised of a generally tubular body 422, having adistal end 424, a proximal end 426 and a longitudinal axis 428 extendingtherethrough between the distal end 424 and the proximal end 426. Thereis, disposed along the longitudinal axis 428 and defined by thegenerally tubular body 422, a proximal passageway 438, located at theproximal end 426 of the adapter 420 and a distal passageway 430, locatedat the distal end 424 of the adapter 420. The proximal passageway 438 isin fluid connection with the distal passageway 430. There is, located inthe proximal passageway 438, at least one rib 437, extending from thetubular body 422 towards the longitudinal axis 428. While FIG. 8 showsthree ribs 437, those skilled in the art will recognize that more orless than three ribs 437 may be used. While the ribs 437 in the currentembodiment are pointed, those skilled in the art will recognize thatother shapes, such as rounded, may be utilized for the ribs 437.

There is located near the distal tip 424, a tapered portion 432, wherethe distal passageway 430 decreases in size moving distally along thelongitudinal axis 428 to a distal opening 433, located at the distal tip424. To engage the trocar 410 with the adapter 420, the distal tip 412of the trocar 410 is inserted into the proximal passageway 438 of theadapter 420 and the trocar 410 is slid distally through the adapter 420.The distal opening 433 is sufficiently large enough to allow thelongitudinal shaft 418 of the trocar 410 to pass through as the trocar410 is slid distally through the adapter 420. The distal opening 433 ofthe adapter 410 is smaller in diameter than the proximal end 414 of thetrocar 410 but larger in diameter than the longitudinal shaft 418 of thetrocar 410. The tapered portion 432 of the adapter 420 is sized tofrictionally engage the beveled portion 416 of the trocar 410 after thelongitudinal shaft 418 of the trocar 410 has been slid through theadapter 420 thereby restricting the proximal end 414 of the trocar 410from passing through distal opening 433 when the trocar 410 is slidthrough the adapter 420. The trocar 410 and the distal opening 433 eachhave a generally circular cross-section, when the cross-sectional viewis taken in a plane that is perpendicular to the longitudinal axis 428.There are a plurality of legs (with only legs 434 a, 434 b being visiblein FIG. 8) extending proximally from the tubular body 422 and aredisposed about the circumference, that define the proximal passageway438. Located on the plurality of legs is a plurality of stops (with onlystops 435 a, 435 b being visible) that project outwardly from thelongitudinal axis 428. The legs generally are tapered at an angle thatis similar to the angle β₂ shown in FIG. 2.

Referring back to FIG. 8, there are a plurality of bumps 450, locatedproximally of the legs 434 a, 434 b disposed about the outside of thetubular body 422 of the adapter 420 and projecting outward away from thelongitudinal axis 428. The bumps 450 are sized to restrict movement ofthe slider 420: however, the bumps 450 are not large enough tocompletely prohibit movement of the slider 420 thereover. Similar to thedisclosures in the other embodiments mentioned herein, the slider 440 issized to frictionally engage the legs 434 a, . . . 434 d when slidproximally towards the stops 435 a, . . . 435 d. Because of the taper ofthe legs when the slider 440 is slid proximally, the legs are pressedtowards the longitudinal axis 428. It is preferable that the slider 440have a range of motion, between the bumps 450 and the stops that isabout two millimeters, however, those skilled in the art will recognizethat the slider 440 may have a range of motion greater or less than twomillimeters while still performing the same function.

The operation of the fourth embodiment of the assembly 400 issubstantially similar to the operation of the other embodimentsdescribed herein. However, because the proximal end 414 of the trocar410 is retained within the distal end 424 of the adapter 420 by thetapered portion 432, the trocar 410 must be inserted into the adapter420 prior to inserting the catheter lumens 50, 52 into the adapter 420.

A fifth embodiment of the present invention is shown in FIGS. 9 and 9 a.In this embodiment, there is a catheter tunneler adapter assembly 500having a trocar 510, an adapter 520 and a slider 540 slidably disposedabout the adapter 520. The trocar has a distal tip 512, a proximal end514 and a longitudinal shaft 513 extending therethrough between thedistal tip 512 and the proximal end 514. Although FIG. 9 shows thedistal tip 512 to be rounded, those skilled in the art will recognizethat the distal tip 512 may be pointed. Although FIG. 9 shows thelongitudinal shaft 513 having a bend, those skilled in the art willrecognize that the longitudinal shaft 513 may be straight. Located atthe proximal end 514 of the trocar 510 is a first rib 515 and a secondrib 517. The first rib 515 and the second rib 517 are separated fromeach other by a circumferential groove 516. The circumferential groove516 does not have uniform depth and is partially flattened to restrictthe trocar 510 from spinning in the adapter 520 after assembly. AlthoughFIG. 9 a shows a catheter tunneler adapter assembly 500 having a roundcross-section, those skilled in the art will recognize that the assembly500 may have a cross-section having a shape other than round.

The adapter 520 is comprised of a generally tubular body 522 having adistal end 524, a proximal end 526 and a longitudinal axis 528 extendingtherethrough between the distal end 524 and the proximal end 526. Thegenerally tubular body 522 of the adapter 520 is tapered so that theproximal end 526 is larger than the distal end 524. A plurality of legs523 a, 523 b, 523 c and 523 d extending proximally about thelongitudinal axis 528 are located at the proximal end 526 of the adapter520. A proximal passageway 530 is disposed about the longitudinal axis528, and is defined by the tubular body 522 located at the proximal end526 of the adapter 520. Located at the proximal end 526 of the adapter520, and extending towards the longitudinal axis 528 is a plurality ofbarbs 527.

A distal passageway 532 is located at the distal end 524 of the adapter520. The distal passageway 532 is defined by the generally tubular body522. Located inside of the distal passageway 532 are a first recess 533and a second recess 535. Located between the first recess 533 and thesecond recess 535 is a distal tab 534. Preferably, the first recess 533is sized to lockingly accommodate the first rib 515 of the trocar 510and the second recess 535 is sized to lockingly accommodate the secondrib 517 of the trocar 510, while the distal tab 534 is sized to fit intothe circumferential groove 516 of the trocar 510. The distal tab 534 ispartially flattened across its circumference to correspond to theflattened areas in the circumferential groove 516 of the trocar 510.

The slider 540 has a distal end 542, a proximal end 544 and a generallytubular body 546 extending therethrough between the distal end 542 andthe proximal end 544. A longitudinal passageway 548 is disposed betweenthe distal end 542 and the proximal end 544 and defined by the generallytubular body 546. Preferably the longitudinal passageway 548 has aproximal passageway 550, extending distally from the proximal end 544and a distal passageway 552, extending proximally from the distal end542. Preferably, where the distal passageway 552 and the proximalpassageway 550 meet, there is a transition slope 554, wherein thecross-sectional area of the longitudinal passageway 548 decreases whilemoving distally between the proximal passageway 550 and the distalpassageway 552. The distal passageway 552 further decreases incross-sectional area approaching the distal end 542. Preferably thedistal passageway 552 is sized to frictionally engage the distal end 524of the adapter 520 and has a cross-sectional area that is smaller thanthe cross-sectional area of the proximal end 526 of the adapter 520.Preferably, the proximal passageway 550 has a cross-sectional area thatis slightly larger than the cross-sectional area of the proximal end 526of the adapter 520.

In use, the fifth embodiment of the catheter tunneler adapter assembly500 is preferably used with a coaxial catheter, such as the Free Flow™catheter, manufactured by Medical Components, Inc. of Harleysville, Pa.Preferably, during manufacturing, the proximal end 514 of the trocar 510is lockingly inserted into the distal passageway 532 of the adapter 520.During insertion, the flattened portion of the circumferential groove516 is aligned with the corresponding flat portion of the distal tab534. The slider 540 may be disposed about the adapter 520 duringmanufacture, or the assembly 500 may be sold in pieces and the slider540 may be disposed about the adapter 520 during post-sale assembly,prior to use. In use, a coaxial catheter 60 is inserted into theproximal passageway 530 of the adapter 520. The coaxial catheter 60 hasa tip lumen 62 and an outer lumen 64. Those skilled in the art willrecognize that the assembly may be used to grip a coaxial catheter 60having a stylet (not shown) as well as a coaxial catheter 60 having nostylet. The slider 540 is then slid distally about the adapter 520 sothat the transition slope 554 engages the outer surface of the adapter520, thereby compressing the plurality of legs 523 a, 523 b, 523 c and523 d towards each other and the longitudinal axis 528 and retaining thecatheter 60 in the proximal passageway 530. Proximal passageway 550 ofthe slider defines an extended sheath section extending to proximal end544, that will ensheathe a length of the catheter extending from theadapter's proximal end. Preferably, the coaxial catheter 60 is insertedfar enough into the proximal passageway 530 of the adapter 520 that theplurality of legs 523 a, 523 b, 523 c and 523 d, when compressed by theslider 520, grip the outer lumen 64. Those skilled in the art willrecognize that the adapter 520 may also be constructed to grip the tiplumen 62. When the slider 540 is slid distally about the adapter 520,the distal passageway 552 of the slider 540 frictionally engages theouter surface of the adapter 520. Although this embodiment of thecatheter tunneler adapter assembly 500 is described as being operated totunnel a coaxial catheter 60, those skilled in the art will recognizethat the adapter assembly 500 may be used to tunnel any other type ofcatheter configuration as well.

It will be appreciated by those skilled in the art that changes could bemade to the embodiments described above without departing from the broadinventive concept thereof. It is understood, therefore, that thisinvention is not limited to the particular embodiments disclosed, but itis intended to cover modifications within the spirit and scope of thepresent invention as defined by the appended claims.

1. A method for tunneling a catheter through a patient, comprising: a.providing: a catheter having at least one lumen, each of the at leastone lumens having a distal end and a proximal end; a trocar having adistal end and a proximal end; an adapter having a distal end, aproximal end having a proximal opening, the proximal opening leading toa longitudinal passageway extending at least an extended distance intothe proximal end, a connector section adjacent the adapter distal endfor releasably connecting the trocar to the adapter distal end; and aslider for cooperating with the adapter proximal end for releasablyrestraining the at least one lumen within the longitudinal passagewaywhen inserted into the proximal opening; b. inserting a first end of theat least one lumen into a patient's vessel; c. connecting the proximalend of the trocar to the adapter; d. inserting a second end of the atleast one lumen into the proximal opening of the adapter; e. moving theslider into position over the adapter proximal end for releasablyrestraining the at least one lumen second end within the longitudinalpassageway; and f. tunneling the catheter.
 2. The method according toclaim 1, wherein the distal end of the at least one lumen is insertedinto the patient's vessel prior to tunneling the at least one lumen. 3.The method according to claim 1, wherein the at least one lumen istunneled prior to inserting the distal end of the at least one lumeninto the patient's vessel.
 4. A method for tunneling a catheter througha patient, comprising: a. providing: a catheter having at least onelumen, each of the at least one lumen having a distal end and a proximalend; a trocar having a distal end and a proximal end; and an adapterhaving a distal end, a proximal end having a proximal opening, theproximal opening leading to a generally centered longitudinal passagewayextending at least for an extended distance into the proximal end, aconnector section adjacent the adapter proximal end for releasablyconnecting the trocar to the adapter distal end, and a catheter-grippingsection at the adapter proximal end for at least generally surroundingan end portion of the at least one lumen; b. inserting a first end ofthe at least one lumen into a patient's vessel; c. connecting theproximal end of the trocar to the adapter distal end such that theadapter is disposed between the trocar and the catheter; d. inserting asecond end of the at least one lumen into the proximal opening of thecatheter-gripping section of the adapter for outer surface portionsthereof to be gripped by the catheter-gripping section; e. moving thecatheter-gripping section of the adapter proximal end into grippingengagement with only outer surface portions of the at least one lumen,thereby releasably connecting the adapter with the at least one lumensecond end within the longitudinal passageway; and f. subsequentlytunneling the catheter by forming a subcutaneous tunnel with the trocarand simultaneously pulling the catheter second end therethrough.
 5. Themethod of claim 4, wherein the step of moving the catheter-grippingsection includes radially reducing the inner diameter of the adapterproximal end by positioning a surrounding component into position aroundand in pressing engagement with outer surfaces of the adapter proximalend.
 6. The method of claim 5, wherein the positioning step is moving aslider along the adapter to surround the adapter proximal end.
 7. Themethod of claim 4, comprising the further step, after tunneling, ofreleasing the adapter from engagement with engaged outer surfaces of theat least one catheter lumen second end.